Dust-separating fan.



J. MCDANIEL.

n'us SEP/RATING FAN.

APPLICATION FILED IUNE 5,1915.

3 SHEETS-SHEET l.

; L BWM@ I. IVICDANIEL.

DUST SEPARATING FAN.

APPLICATION FILED IUNE 5,19I5.

'lwm Patented Apr. 17, 1917.

3 SHEETS-SHEET 2.

am@ WW/ MDM l. IVICDANIEL.

DUST SEPARATING FAN.

APPLICATION FILED JUNE 5,191'5.

19222;?75@ Patented Apr. 17, 1917.

3 SHEETS-SHEET 3.

WWEMMM .@ANL 50 F/ 4. WM

JAMES MGDANIEL, OF M'INNEAPGLIS, MINNESOTA..

DUST-SEPARATING FAN.

Application filed .Tune 5, 1915.

To all whom t may concern it known that l, Sums MCDANIEL, citizen of the United ltates, resident of llinneapolis, county of Hennepin, State of Minnesota, have invented certain newl and useful linpr-ovements in Dust-Separating l? ans, ot which the following is a specification. n

My invention relates to dust separators applicable for use with various lrinds of machines, particularly milling machinery, and the object of the invention is to provide a separator which will effect thorough sepa ration of the light as well as the heavier particles or' dust and dispense entirely with the ordinary cloth dust collectors now in general use.

il further object is to provide a separator olf comparatively small, compact construction which can be easily mounted on or within the asing of the machine.

@ther objects or the invention will appear from the following etailed description.

rl`he invention consists generally in various constructions and combinations, all as hereinafter described and particularly pointed out in the claims.

ln the accompanying drawings forming part of this specification, i

Figure 1 is a vertical sectional View illustrating the application of the collector to the casing of a machine,

llig. 2 is a sectional view, taken on a line at right angles substantially to the section line of Fig. 1,

Fig. 3 is a view on the section line y/-g/ of l? ig. 2,

Fig. 4 is an enlarged detail View of the collector,

Fig. 5 is a view on the section line mha' of Fig. 2,

Fig. 6 is a detail sectional view, showing the hopper-like device in which the material separated from the air is collected.

ln the drawing, 2 represents the casing of a machine, in which the dust separator is mounted. rllhis machine may be a purifier or any other'machine'in connection with which it is desirable to use a dust separator. 3 is a shaft, having' bearings 4 in the machine frame and provided with a driven pulley Mounted on this shaft is a blast lan 7 having a casing 8 provided with central openings or eyes 9. The casing 8 has an air trunk 1G communicating therewith and leading to a suitable receptacle, such as Specification of Letters Patent.

Patented Apr. 1*?, 1917.

Serial No. 32,316.

a globe 11, having perforations 12 therein. rllhe trunk is provided with a valve 13. This Olobe may be located at any suitable distance from the fan and its function will be hereinafter described more in detail.

The fan casing is supported in the frame of the machine by suitable means, such as the arms 14. The shaft 3 is provided with right and left hand threads upon opposite sides of the fan, with which the interiorly threaded hubs 15 engage. These loops are held in place by set screw collars 16. When these set screws are loosened, the hubs may be revolved on the shaft to move them toward or from the fan casing. Spiders 17 are loosely mounted on the shaft 3 and a member 18, preferably ot .sheet metal in the form, substantially, of a truncated cone, is provided on each side of the casing with its inner larger end secured to the spider 17 adjacent to and substantially covering the eye of the fan, while its outer end is secured to the inner portion or". the hub 15 on that side of the fan. A. .member 19 is provided on each side of the fan casing concentric with the' member 18, also in the form of a truncatedcone and spaced from said member to form a flaring annular passage 2O between said members, the inner end of each member 19 being secured to a ring 2l. Blades 22 are interposed between said members and secured thereto and support the outer member in its concentric relation with respect to the inner member. The major diameter of the members 19 upon opposite sides of the fan casing` corresponds substantially for convenience to the diameter of the fan casing, while, as stated above, the major diameter of the member 1S corresponds to the diameter of the eves of the fan casing.

Between the rings 21 and the casing comparatively narrow cracks or gaps 23 are provided, and plates 24 are interposed between the coneshaped member 18 and the fan casing and have gaps 25 between their outer edges and the walls oi the members 19, said plates having centra-l openings 26 communicating1 with the eyes of the fan casing. Rings 2'? are secured to the plates 24 and extend diagonally through the space between said plates and the fan casing and serve to deflect the dust passing through the gaps 25 toward the gaps or openings 23, as will hereinafter appear.

lt will be noted that the exit gap 23 is a considerable. distance from the inlet opening to the fan casing and that the walls converge toward this gap and the wall Qet extends substantially across thel space between the inner and outer cone-shaped members and thereby the dust directed by the converging walls to the exit gap will be outside the zone of iniiuence of the air entering the inlet opening of the casing and consequently there will be no danger of the dust being sucked into the casing, which might result if the exit gap was disposed near the entrance to the fan. I regard this location of the dust eXit gap as an important feature of the invention.

' The passages 20 communicate with a A chamber 28 formed rin the casing of the machine and provided with a suitable housing 29 and from Vthis chamber 28 the dust laden air is drawn into the passages 2O on each side of the fan easing. rlhese passages, as shown plainly in Fig. 2, extend or flare inwardly and allow the incoming air currents to spread out as they approach the fan casing and the cone-shaped members, and the fan will be operated at such a speed that the specific gravity of the particles of dust will be multiplied many times, depending, of course, on the velocity of the fan, and through centrifugal force both the light and heavy particles of dust will be thrown outwardly against the walls 19 and will follow these walls inwardly through the gaps 23 while the air currents, freed from the dust held in suspension when they enter the passages 20, will be drawn through the openings 26 into the fan casing and from thence will pass out through the trunk to t-he perforated member 11. rlhis member prefer to designate as a diffuser, as it operates as an escape for the air without creating any blast7 but allows it to flow out through the perforations and gently spread around in the mill or other place where the diffuser may be located.

The separation will be so complete through the action of the rapidly revolving fan and the separating passages 20, that the air entering the diffuser will be practically free from dust. The dust discharged through the gaps 23 will enter the chambers 30 formed by the casings 31 and in these chambers a Cyclonic effect will be produced, a small percentage of air passing through the gaps with the dust. The casings 31 are hopper-shaped, and the dust will be whirled around therein at the outside of the air currents or eddies against the walls of the. casing and will follow these walls, driven by the air currents, until the exit openings 32 are reached leading to a spout 33 having a dead air chamber 84 and a controlling valve 34. These casings 31, as indicated plainly in Fig. 2, encircle the fan casing and the inner portions of the truncated members 18 and 19, and gaps 35 of suitable width are provided between these casings and the walls of the member 19 and through these gaps the currents of air in the chamber 30 will flow and entering the chambers 28, will mingle with the dustladen air currents therein and flow again through the passages 20 toward the fan.

The velocity of the fan may be varied to suit different conditions,-the higher the speed the more effective the centrifugal force will be to separate the dust particles from the incoming air currents. Should the fan be operating at a certain speed and the separation be not as effective as desirable, the velocity can be increaseduntil the air discharged into the diffuser is practically free from dust particles.

The narrow gap or passage through which the dust is discharged bycentrifugal force has the stationary wall of the casing on one side and the revolving inner end of the outer cone on the other side, and consequently, even though this gap may be com- Vaaiatively narrow, there is no chance for the dust to clog or bridge in the gap and l have found by actual test that seeds and small particles too large to pass freely through the gap will be crushed between the walls and discharged. By the adjustment of the cones toward and from the fan the width of the gap can beV increased or decreased, as desired.

In the operation of this separator, the passages 20 are mounted to communicate with the interior of a dust-bearing casing and when the fan is set in motion, currents of air will be established through the chainber leading to the passages 2O and the dustladen air will be drawn into these passages where, through the rapid revolution of the truncated cones, the material will be thrown outwardly against the outer walls of the cones, the expansion of the air currents as they approach the fan facilitating the separation. The high velocity of revolution of the cones will throw the fine particles of dust against the cone walls, while the inward suction of the air currents toward the fan will be suliicient to cause the dust lying against the walls to slide inwardly toward the exit gapsand pass through them into the chamber 30, from whence the dust will be dischargedand the air will escape, as described.

The device may, of course, be made in various sizes to suit different conditions and in various ways the details of construction may be varied and still be within the scope of my invention.

l claim as my invention:

1. A dust separator comprising a fan and casing therefor having an Vair inlet opening and concentric members spaced apart *and arranged opposite said opening, said members having a dust passage formed between them and a dust inlet opening thereto at les their outer ends, the inner member being opposite and adjacent said inlet opening, the outer member eing spaced from said casing and cooperating therewith to form a narrow dust gap, said member and the wall of said casing converging toward said gap to form a peripheral pocket and into which pocket the particles of dust are directed by centrifugal force, and a dust chamber encirclin' said casing and receiving the dust from said gap.

2. A dust separator comprising a fan and casing therefor having air inlet openings in its opposite walls, concentric, substantially cone-shaped members arranged in pairs opposite said openings and having dust inlet openings and passages formed between them, walls provided at the inner end of said members and extending across the space between them, the outer members being spaced from said walls to form narrow dust eXit gaps, said walls and said outer members converging toward said gaps to form peripheral pockets and direct the dust thrown outwardly through centrifugal force into said gaps, the inner members being spaced from the edges of said openings and adjacent thereto to provide air passages into said casing.

3. A dust separator comprising a fan, a casing therefor having a central air inlet opening, substantially cone-shaped members arranged opposite said opening, said members being spaced apart and having a dust inlet opening at their outer ends, the inner end of said inner member being opposite said inlet opening and spaced from the wall of said casing at the edge of said opening to form an air passage, the inner end of the outer member having a comparatively narrow eXit gap formed between it and the outer portion of the wall of said casing, said wall extending across the space between said inner and outer members, a peripheral pocket with converging walls being formed by the wall of said casing and said outer member, whereby the dust thrown outwardly by centrifugal force will be directed to said exit gap and outside the zone of influence of the air entering the inlet opening of said casing.

4.. A dust separator comprising a. fan and casing .therefor having an air inlet opening in its side wall, concentrically arranged cone-shaped members mounted opposite said opening, said members being spaced apart to form a dust passage between them and having a dust inlet opening at their outer ends, said inner member being adjacent the edge of said inlet opening to form an air passage between them, an eXit dust gap being formed between said outer member and the wall of said casing through which the dust thrown outwardly by centrifugal force may escape, a peripheral pocket with converging walls being formed by the wall of said casing and said outer member, whereby t-he dust thrown outwardly by centrifugal force will be directed to said dust gap and out of the path of the air entering the inlet opening' of said casing.

5. A dust separator comprising a fan, a casing therefor having inlet openings, coneshaped members mounted to revolve on opposite sides of said casing and having passages there-between, a dust chamber com` municating with said passages at their outer ends, means to subject the dust held in suspension in the air passing through the passages to centrifugal force, means providing exit openings at the inner portions of said passages through which the dust is discharged and means providing communica tion between the inner portions of said passages and the interior of the fan casing, a dustegathering chamber encircling said casing and having a dust outlet opening and also having air escape openings adjacent to the walls of said cone-shaped members.

G. A dust separator comprising a fan and a stationary casing therefor lia-ving inlet openings upon opposite sides of said fan, inner and outer members concentrically arranged with a passage between them upon opposite sides of said casing, said inner members being adjacent to said inlet openings and spaced therefrom, said outer members having their inner edges close to the walls of said stationary casing, with a narrow gap or passage formed between them, both of said members increasing in diameter from their outer toward their inner ends, whereby the passages formed between said inner and outer members will increase in cross sectional area toward the inner ends of said members, the dust entering said passage being directed by centrifugal force outwardly therein and passing with a portion of the air outwardly through said gaps or passages, the coperation of the moving inner edges of said outer members with the stationary surfaces of said casing preventing bridging or clogging of the dust between them, said casing extending across the passage between said members and forming with the outer member a peripheral pocket communicating with said gap and at a distance from the inlet opening to said casing.

7. A dust separator comprising a fan, a casing therefor having an inlet opening, cones concentrically mounted to encircle said opening and spaced apart to form an air passage between them, said passage being open at its outer end to allow currents of dust laden air to flow therein through the suction of the fan, the dust being thrown by centrifugal force against the wall of the outer cone, a comparatively narrow dust gap being formed between the inner end of the outer cone and said casing and through which gap the dust and a portion of the air is discharged, said outer cone and the wall of said casing having a relative revolving movement, whereby clogging of the dust in said gap is prevented, said inlet opening being adjacent and opposite said inner cone and at a distance from said gap or opening equal substantially to the width of the space between said cones.

8. A dust separator comprising a shaft, a fan and casing therefor having air intake openings in its side walls, cones concentrically mounted on said shaft and spaced apart to form air intake openings between them, the outer ends of said openings communicating with dust passages and blades provided in said openings between said cones, means partially closing the openings between said cones at the inner ends thereof and having passages through which the particles of dust are directed by centrifugal force, said. closing means having a central opening communicating` with the space between said cones and with said fan.

9. A dust separator comprising a shaft, a fan mounted thereon, a casing for said fan having an opening in its side wall, a. hub mounted on said shaft and having a threaded connection therewith for longitudinal adjustment, cones concentrically supported on said hub and spaced apart to form a dust intake passage between them and having their inner ends encircling the opening in said casing, said cones and casing having a relative revolving movement, a dust gap being provided between the inner end of said outer cone and said casing, through Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

the width of the passage between said cones,

for the purpose specified.

l0. A dust separator comprising a fan andV casing therefor having an inlet opening, a member mounted to revolve adjacent to said opening and having a dust intake passage into which the dust-laden air is drawn by the revolution of said fan, the dust being subjected to centrifugal action in said passagey a comparatively narrow gap or opening being provided at the inner end of said member through which gap the dust is discharged, the walls of said gap .being relatively movable, whereby clogging of the dust therein is prevented, said inlet opening being spaced from said gap a distance substantially equal to the width of said dust intake passage, whereby the'particles of Vdust following the wall of said member to said gap will be outside the suction iniiuence substantially of the air entering said casing.

In witness whereof, have hereunto set my hand this 2d day of J une, 1915.

JAMES MCDANIEL.

Witnesses:

GENEVIEVE E. SoREN'sEN, EDWARD A. PAUL.

Washington, D. C. 

